/* assets/css/style.css */
@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&family=Plus+Jakarta+Sans:wght@400;500;600;700&display=swap');

:root {
    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --primary-light: #eef2ff;
    --primary-gradient: linear-gradient(135deg, #6366f1 0%, #4f46e5 50%, #3730a3 100%);
    
    --secondary: #0ea5e9;
    --secondary-gradient: linear-gradient(135deg, #38bdf8 0%, #0284c7 100%);
    
    --accent: #10b981;
    --accent-light: #d1fae5;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
    --danger: #ef4444;
    --danger-light: #fee2e2;

    --bg-main: #f8fafc;
    --bg-surface: #ffffff;
    --bg-card: rgba(255, 255, 255, 0.95);
    
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    
    --border-subtle: #e2e8f0;
    --border-focus: #6366f1;
    
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --shadow-glow: 0 0 25px -5px rgba(79, 70, 229, 0.35);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 18px;
    --radius-xl: 24px;
    
    --transition-fast: 0.15s ease;
    --transition-base: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Plus Jakarta Sans', sans-serif;
    background-color: var(--bg-main);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.5;
    background-image: 
        radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.08) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(14, 165, 233, 0.08) 0px, transparent 50%),
        radial-gradient(at 50% 50%, rgba(16, 185, 129, 0.04) 0px, transparent 50%);
    background-attachment: fixed;
    display: flex;
    flex-direction: column;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Outfit', sans-serif;
    color: var(--text-primary);
    font-weight: 700;
}

/* Header & Nav */
.header-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 2rem;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-subtle);
    position: sticky;
    top: 0;
    z-index: 50;
}

.brand-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--text-primary);
}

.logo-icon {
    width: 42px;
    height: 42px;
    background: var(--primary-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    box-shadow: 0 4px 12px rgba(79, 70, 229, 0.3);
}

.brand-name {
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.admin-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: white;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition-fast);
}

.admin-link:hover {
    background: var(--primary-light);
    color: var(--primary);
    border-color: #c7d2fe;
}

/* Main Container */
.main-wrapper {
    flex: 1;
    max-width: 900px;
    width: 100%;
    margin: 2rem auto;
    padding: 0 1.25rem;
}

/* Hero Section */
.hero-header {
    text-align: center;
    margin-bottom: 2rem;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.35rem 0.85rem;
    background: var(--primary-light);
    color: var(--primary);
    border-radius: 9999px;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.75rem;
}

.hero-title {
    font-size: 2.25rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, #0f172a 0%, #334155 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-desc {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Card Container */
.submission-card {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    padding: 2.25rem;
    box-shadow: var(--shadow-xl);
    position: relative;
    overflow: hidden;
}

.submission-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 6px;
    background: var(--primary-gradient);
}

/* Form Steps / Sections */
.form-section {
    margin-bottom: 2rem;
    padding-bottom: 1.75rem;
    border-bottom: 1px solid var(--border-subtle);
}

.form-section:last-child {
    border-bottom: none;
    margin-bottom: 1.5rem;
    padding-bottom: 0;
}

.section-title-wrap {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.25rem;
}

.section-number {
    width: 28px;
    height: 28px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    font-weight: 700;
}

.section-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 0.15rem;
}

/* Form Controls */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.25rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    position: relative;
}

.form-label {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.form-label-hint {
    font-size: 0.75rem;
    font-weight: 400;
    color: var(--text-muted);
}

.form-select, .form-input, .form-textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 0.95rem;
    font-family: inherit;
    color: var(--text-primary);
    background: white;
    border: 1.5px solid var(--border-subtle);
    border-radius: var(--radius-md);
    outline: none;
    transition: var(--transition-fast);
}

.form-select:focus, .form-input:focus, .form-textarea:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.15);
}

.form-textarea {
    resize: vertical;
    min-height: 80px;
}

/* Activity Details Box */
.activity-info-box {
    background: #f1f5f9;
    border-left: 4px solid var(--primary);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    padding: 1rem 1.25rem;
    margin-top: 1rem;
    display: none;
    animation: fadeIn 0.3s ease;
}

.activity-info-title {
    font-weight: 700;
    color: var(--text-primary);
    font-size: 0.95rem;
    margin-bottom: 0.25rem;
}

.activity-info-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.activity-meta-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.meta-tag {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.25rem 0.6rem;
    background: white;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    border: 1px solid var(--border-subtle);
}

/* Autocomplete Students Search */
.autocomplete-container {
    position: relative;
}

.autocomplete-dropdown {
    position: absolute;
    top: calc(100% + 6px);
    left: 0;
    right: 0;
    background: white;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    max-height: 220px;
    overflow-y: auto;
    z-index: 100;
    display: none;
    list-style: none;
}

.autocomplete-item {
    padding: 0.75rem 1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: var(--transition-fast);
    border-bottom: 1px solid #f8fafc;
}

.autocomplete-item:hover, .autocomplete-item.active {
    background: var(--primary-light);
    color: var(--primary);
}

.autocomplete-item-name {
    font-weight: 600;
    font-size: 0.9rem;
}

.autocomplete-item-email {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Selected Student Chips */
.selected-students-grid {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-top: 1rem;
}

.student-chip {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    background: white;
    border: 1.5px solid #e0e7ff;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-fast);
    animation: slideUp 0.2s ease;
}

.student-chip-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.student-chip-avatar {
    width: 36px;
    height: 36px;
    background: var(--primary-light);
    color: var(--primary);
    font-weight: 700;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
}

.student-chip-details h5 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
}

.student-chip-details p {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.student-chip-remove {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.4rem;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-fast);
}

.student-chip-remove:hover {
    color: var(--danger);
    background: var(--danger-light);
}

.team-count-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.8rem;
    font-weight: 600;
    padding: 0.25rem 0.6rem;
    border-radius: 9999px;
    background: #f1f5f9;
    color: var(--text-secondary);
}

/* Dropzone Styles */
.dropzone-container {
    border: 2px dashed #cbd5e1;
    border-radius: var(--radius-lg);
    padding: 2.25rem 1.5rem;
    text-align: center;
    background: #fafafa;
    cursor: pointer;
    transition: var(--transition-base);
    position: relative;
}

.dropzone-container:hover, .dropzone-container.dragover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.dropzone-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto 1rem;
    background: white;
    color: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
    transition: var(--transition-fast);
}

.dropzone-container:hover .dropzone-icon {
    transform: translateY(-3px) scale(1.05);
}

.dropzone-title {
    font-weight: 700;
    font-size: 1.05rem;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.dropzone-sub {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.file-input-hidden {
    position: absolute;
    width: 0;
    height: 0;
    opacity: 0;
    pointer-events: none;
}

/* File List Preview */
.files-preview-list {
    margin-top: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.file-preview-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.6rem 0.9rem;
    background: white;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    font-size: 0.85rem;
    animation: fadeIn 0.2s ease;
}

.file-preview-info {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    overflow: hidden;
}

.file-preview-icon {
    color: var(--primary);
}

.file-preview-name {
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 320px;
}

.file-preview-size {
    color: var(--text-muted);
    font-size: 0.75rem;
}

.file-preview-remove {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.3rem;
    border-radius: var(--radius-sm);
    transition: var(--transition-fast);
}

.file-preview-remove:hover {
    color: var(--danger);
    background: var(--danger-light);
}

/* Submit Action Button */
.btn-submit {
    width: 100%;
    padding: 1rem 1.5rem;
    background: var(--primary-gradient);
    color: white;
    font-family: inherit;
    font-size: 1.05rem;
    font-weight: 700;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    box-shadow: 0 4px 14px rgba(79, 70, 229, 0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    transition: var(--transition-base);
    margin-top: 1.5rem;
}

.btn-submit:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(79, 70, 229, 0.5);
}

.btn-submit:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Spinner */
.spinner {
    width: 20px;
    height: 20px;
    border: 2.5px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
    display: none;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(4px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Success Receipt Modal / Card */
.receipt-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1.5rem;
    z-index: 1000;
    display: none;
    animation: fadeIn 0.25s ease;
}

.receipt-card {
    background: white;
    border-radius: var(--radius-xl);
    width: 100%;
    max-width: 580px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    overflow: hidden;
    position: relative;
    animation: slideUp 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.receipt-top {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    color: white;
    padding: 2rem;
    text-align: center;
}

.receipt-check-icon {
    width: 64px;
    height: 64px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
}

.receipt-title {
    font-size: 1.5rem;
    font-weight: 800;
    color: white;
}

.receipt-body {
    padding: 1.75rem 2rem;
}

.receipt-code-box {
    background: #f8fafc;
    border: 1.5px dashed var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 0.9rem;
    text-align: center;
    margin-bottom: 1.25rem;
}

.receipt-code-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 700;
    color: var(--text-muted);
}

.receipt-code-value {
    font-size: 1.35rem;
    font-weight: 800;
    color: var(--primary);
    letter-spacing: 0.05em;
}

.receipt-details-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    font-size: 0.9rem;
    border-bottom: 1px solid var(--border-subtle);
    padding-bottom: 1.25rem;
    margin-bottom: 1.25rem;
}

.receipt-details-item {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
}

.receipt-label {
    color: var(--text-muted);
    font-weight: 500;
}

.receipt-val {
    font-weight: 600;
    color: var(--text-primary);
    text-align: right;
}

.receipt-students-box {
    margin-bottom: 1.25rem;
}

.receipt-students-title {
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.receipt-student-tag {
    display: inline-block;
    background: #f1f5f9;
    padding: 0.35rem 0.7rem;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 600;
    margin: 0.2rem;
}

.receipt-btn-close {
    width: 100%;
    padding: 0.85rem;
    background: var(--text-primary);
    color: white;
    font-weight: 700;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition-fast);
}

.receipt-btn-close:hover {
    background: #334155;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    z-index: 2000;
}

.toast {
    background: white;
    color: var(--text-primary);
    padding: 1rem 1.25rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    min-width: 300px;
    border-left: 4px solid var(--primary);
    animation: slideInRight 0.3s ease;
}

.toast.toast-error {
    border-left-color: var(--danger);
}

.toast.toast-success {
    border-left-color: var(--accent);
}

@keyframes slideInRight {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

/* Responsive */
@media (max-width: 640px) {
    .header-nav {
        padding: 0.75rem 1rem;
    }
    .submission-card {
        padding: 1.5rem 1.25rem;
    }
    .hero-title {
        font-size: 1.75rem;
    }
}